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What might be your best bet in identifying the attached, please?

Is it a lab-created spinel?, a green garnet or tourmaline? Thanks

N.B.:the stone has no inclusions

170 Carca 750+eagle+ 13x13mm ~150|500x500

There is just no way to ID a stone from a picture…and why would you believe someone you didn’t know who did? You can more or less eliminate tourmaline if it doesn’t show dichroism…a different color from the side vs thru the table. It could be syn spinel, green garnet (unlikely, most tsavorite does not have a blue secondary tone), tourmaline, syn emerald, glass, and there are probably other possibilities I haven’t thought of. A refractometer reading would probably settle the ID for anyone with some experience. Check with your local Gem and Mineral Society for someone who would help you out with this gratis. Or take it to their gem and mineral show, where they are likely to run a “free ID” booth. Or perhaps a local jeweler would look at it, but don’t place too much stock in what they say unless you see them test it and explain their ID. There are jewelers who don’t know much gemology, still, in this day and age…-royjohn

Thank you for your help…
Since my Presidium reads at the lower end of Jadeite/spinel, I’m proceeded through elimination–
No inclusion, no dichroism, some blue tone. At this time, I do not have access to a refractometer which, you’re right, would settle the score. And my annual meeting of the Mineral society in Paris was cancelled due to Covid. guess I’ll have to wait till next year when it meets again. For the moment, I’ll put it under lab-created spinel for lack of a better clue!. Thank you again!

Can you determine the flavor of this muffin from the photo? Your gemstone could be glass, YAG, Nanosital, synthetic quartz, synthetic spinel, synthetic sapphire, tourmaline, chrysoberyl, moldavite, vesuvianite (aka) idocrase, Oregon sunstone, zoisite, etc. - and, Presidium is USELESS for accurately determining colored gemstone id. Muffin

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Looks like carrot?


Thanks for the humour!
Seriously, can you tell us what Presidium is good for, then. Thanks!

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Well I bought a presidium gem tester to see 20 stone and 0 correct. I can sell it to you if you would like.

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Looks like pumpkin to me :tongue::cupcake:


Could be Chrome Diopside

Carrot cake, 100% certain

i am only a collector so by no means an expert but for me I use it to check my stones post buying them so I disagree that it is useless. If you are buying something and it confirms what it is it then you are better off than taking the word of the seller.

Thank you. I am a common sense person, so I agree with you!

Here’s a link to an article that explains perfectly what gem testers are actually able to to do.

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Yep, I was suckered into paying out the wazoo for an expensive colored gemstone tester and it did me no good. My microscope tells me more than those things do. So many other cheaper tools out there that can do so much more. :rofl:

Thanks. Very helpful!

Not sure. I think you need a more close up high resolution photo of the stone. I’m not sure what gem it might be but judging from the bubbles it looks like it might be synthetic.

Thanks! I think so also…maybe synthetic spinel